As a type of polymer thin film forming method, vacuum deposition polymerization has been known (e.g., Japanese Unexamined Patent Application Publication No. S61-78463). In vacuum deposition polymerization, a polymer thin film is formed by vacuum-evaporating two or more kinds of monomers and polymerizing the monomers, for example, on a substrate in vacuum. It is possible to control, in nano order, the film thickness of a polymer thin film formed by such vacuum deposition polymerization.
However, raw materials that may be used for vacuum deposition are limited, and when a plurality of raw materials are used, it has problems, such as difficulty in the control of reactivity. There are also problems, such as the requirement of vacuum equipment and the complicated control of a polymerization reaction, and thus such vacuum deposition has not been necessarily satisfactory in all cases.
In addition, the polymerization apparatus used for the vacuum deposition polymerization also has problems, such as the requirement of vacuum equipment and the complicated control of a polymerization reaction. Therefore, there has been a demand for a polymerization apparatus that is easy to control and capable of film thickness control in nano order to replace the vacuum deposition polymerization apparatus.